Estimulación cerebral profunda del globo pálido interno en el síndrome de distonía mioclónica: serie de 3 casos y revisión de la literatura / Deep brain stimulation of the internal globus pallidus in myoclonus-dystonia syndrome: a case series and review of the literature

RESUMEN INTRODUCCIÓN: La distonía mioclónica es un trastorno del movimiento con poca prevalencia, pero muy discapacitante, en el cual es frecuente la refractariedad al tratamiento médico. Cómo opción terapéutica se ha planteado la estimulación cerebral profunda, buscando con ello mejorar la función motora, la discapacidad y la calidad de vida de estos pacientes. MATERIALES Y MÉTODOS: Se presentan 3 pacientes con diagnóstico clínico de distonía mioclónica sin confirmación genética, que fueron llevados a estimulación cerebral profunda bilateral del globo pálido interno. RESULTADOS: Se evidenció una mejoría significativa en la evaluación de la escala unificada de mioclonías (80-90 %) y en la escala de distonía de Burke-Fahn-Marsden (tanto en movilidad como en discapacidad). La mejoría clínica se evidenció en los tres pacientes, en periodos de seguimiento que estuvieron entre los 6 meses y los 5 años luego de la estimulación cerebral profunda. DISCUSIÓN Y CONCLUSIONES: Los hallazgos en esta serie de 3 pacientes colombianos son consistentes con lo reportado en la literatura. Sin embargo, aportan información sobre el desenlace de pacientes sin genotipificación sometidos a estimulación cerebral profunda, dado que la eficacia de la intervención en pacientes con distonía sin confirmación genética aún no ha sido determinada, y depende de otros factores como la edad, el tiempo de evolución y el tipo de distonía.

ABSTRACT INTRODUCTION: Myoclonic dystonia is a movement disorder with low prevalence, but very disabling, where refractoriness to medical treatment is frequent. Deep brain stimulation has been proposed as a therapeutic option, seeking to improve motor function, disability and quality of life in these patients. MATERIALS AND METHODS: We present 3 patients with a clinical diagnosis of Myoclonic-Dystonia without genetic confirmation, who underwent bilateral deep brain stimulation of the Globus Pallidus Internus. RESULTS: A significant improvement was evidenced in the evaluation of the unified myoclonus scale (80-90 %) and in the Burke-Fahn-Marsden dystonia scale (both in mobility and in disability). The clinical improvement was evidenced in the 3 patients, in follow-up periods that were between 6 months and 5 years after deep brain stimulation. DISCUSSION AND CONCLUSIONS: Findings in this Colombian case series are consistent with that reported in the literature. However, the current description provides information on the outcome of patients without genotyping undergoing deep brain stimulation, considering that the efficacy of the intervention in these types of patients without genetic confirmation has not been determined and depends on other factors.

Nueva mutación en el gen KMT2B como causa de distonía generalizada de inicio temprano: reporte de caso / Early-onset generalized dystonia caused by a new mutation in the KMT2B gene: Case report

La distonía por mutación en el gen KMT2B es un subtipo recientemente descrito del inicio focal de la enfermedad en los miembros inferiores que, posteriormente, evoluciona a una forma generalizada con compromiso cervical y orofaríngeo, disartria, trastorno secundario de la deglución y discapacidad intelectual. Se describe el caso de una escolar de 10 años de edad, sin antecedentes de consanguinidad ni historia familiar de enfermedad neurológica, que presentó alteración de la marcha y distonía de inicio focal, de curso progresivo a una forma generalizada que afectó sus músculos orofaciales y bulbares con alteración significativa del lenguaje y la deglución. Los estudios metabólicos y sistémicos, incluidas las neuroimágenes, no evidenciaron anormalidades. Se hizo una secuenciación genómica completa y se identificó una nueva variante, probablemente patogénica heterocigota, en el gen KMT2B, la c.1205delC, p.(Pro402Hisfs*5), que causa desplazamiento en el marco de lectura. Este hallazgo explica el fenotipo de la paciente y la distonía de inicio temprano autosómica dominante. Se reporta una nueva mutación heterocigota del gen KMT2B como causa de distonía generalizada de inicio temprano, no reportada en la literatura especializada hasta el momento. El diagnóstico de esta afección tiene implicaciones en el tratamiento y el pronóstico de los pacientes, porque las estrategias terapéuticas tempranas pueden prevenir su rápido deterioro y un curso más grave de la enfermedad.

Introduction: KMT2B-related dystonia is a recently described subtype of focal-onset dystonia in the lower limbs, evolving into a generalized form with cervical, oropharyngeal involvement, dysarthria, swallowing disorder and intellectual disability. Clinical case: We describe the case of a 10-year-old female patient, without a history of consanguinity or neurological disease. She manifested abnormal gait and dystonia with focal onset and progressive course with evolution into generalized dystonia, affecting orofacial and bulbar muscles, significant alteration of language and swallowing. Metabolic and systemic studies, including neuroimaging, were found to be normal. A complete genomic sequencing study was performed identifying a new, probably pathogenic, heterozygous variant in the KMT2B gene, c.1205delC, p. (Pro402Hisfs*5), causing displacement in the reading frame, a finding that explains the patient's phenotype and it is associated to autosomal dominant childhood-onset dystonia-28. Conclusion: We report a new heterozygous mutation in the KMT2B gene as a cause of generalized early-onset dystonia not reported in the literature until the date. The diagnosis of this pathology has implications for the treatment and prognosis of patients, given that therapeutic strategies implemented early can prevent the fast deterioration and severe course of this disease.

Impacto en la calidad de vida del tratamiento de disfonía espasmódica aductora con toxina botulínica A / Impact on the quality of life of the treatment of adductor spasmodic dysphonia with botulinum toxin A

Introducción. La distonía laríngea o disfonía espasmódica se caracteriza por con-tracciones involuntarias de los músculos laríngeos internos que se desencadenan al hablar, siendo la forma aductora la más frecuente. La inyección de toxina botulínica es el manejo de elección. Para evaluar la respuesta a la terapia existen varios instru-mentos validados, uno de ellos es el cuestionario Voice Handicap Index-10 (VHI-10). El objetivo de este estudio es caracterizar a los pacientes con disfonía espasmódica aductora y evaluar el impacto de la toxina en su calidad de vida.Método. Éste se centró en un estudio retrospectivo descriptivo en pacientes adultos con diagnóstico de disfonía espasmódica aductora tratados con toxina botulínica A, en el Hospital Clínico Universidad de Chile (HCUC), en el periodo comprendido en-tre 2013 y 2021. El mismo permitió la obtención de los datos epidemiológicos de los pacientes, a quienes se les solicitó responder la encuesta VHI-10 previo y posterior a un mes de cada inyección de la toxina.Resultados. Se incluyeron 55 pacientes (218 procedimientos). La dosis promedio utilizada fue de 9,18 UI con un intervalo promedio de 7,4 meses. El puntaje VHI-10 promedio en la evaluación inicial fue de 29,4 y posinfiltración de 14,96, siendo esta diferencia significativa (p < 0,000001). En nuestra serie casi un tercio tiene asociada alguna patología neurológica, y se reportó un 3,67% de complicaciones leves y transitorias.Conclusión. La disfonía espasmódica aductora tiene un gran impacto en la calidad de vida de los pacientes, que se reduce significativamente mediante la inyección de toxina botulínica A, procedimiento que ha demostrado ser seguro y eficaz

Introduction. Laryngeal dystonia or spasmodic dysphonia is characterized by in-voluntary contractions of internal laryngeal muscles that are triggered when speak-ing, being the adductor form the most frequent. Botulinum toxin injection is the management of choice. There are several validated instruments to assess response to therapy, one of them is the Voice Handicap Index-10 (VHI-10) questionnaire. The objective of this study is to characterize patients with adductor spasmodic dysphonia and evaluate the impact of the toxin in their quality of life.Method. A descriptive retrospective study was carried out in adult patients with a diagnosis of adductor spasmodic dysphonia treated with botulinum toxin A, between 2013-2021 at the Hospital Clínico Universidad de Chile. The epidemiological data of the patients and the VHI-10 survey were obtained before and after one month of each toxin injection was requested.Results. 55 patients (218 procedures) were included. The average dose used was 9.18 IU with an average interval of 7.4 months. The average VHI-10 score in the initial evaluation was 29.4 and post-infiltration was 14.96, being this difference sig-nificant (p <0.000001). In our series, almost a third had an associated neurological pathology, and 3.67% of mild and transitory complications were reported.Conclusion. Adductor spasmodic dysphonia has a great impact on the quality of life of patients, which is significantly reduced by injecting botulinum toxin A, a pro-cedure that has been shown to be safe and effective

Deep brain stimulation treatment in dystonia: a bibliometric analysis / Estimulação cerebral profunda no tratamento de distonia: uma análise bibliométrica

ABSTRACT Background: Dystonia is a heterogeneous disorder that, when refractory to medical treatment, may have a favorable response to deep brain stimulation (DBS). A practical way to have an overview of a research domain is through a bibliometric analysis, as it makes it more accessible for researchers and others outside the field to have an idea of its directions and needs. Objective: To analyze the 100 most cited articles in the use of DBS for dystonia treatment in the last 30 years. Methods: The research protocol was performed in June 2019 in Elsevier's Scopus database, by retrieving the most cited articles regarding DBS in dystonia. We analyzed authors, year of publication, country, affiliation, and targets of DBS. Results: Articles are mainly published in Movement Disorders (19%), Journal of Neurosurgery (9%), and Neurology (9%). European countries offer significant contributions (57% of our sample). France (192.5 citations/paper) and Germany (144.1 citations/paper) have the highest citation rates of all countries. The United States contributes with 31% of the articles, with 129.8 citations/paper. The publications are focused on General outcomes (46%), followed by Long-term outcomes (12.5%), and Complications (11%), and the leading type of dystonia researched is idiopathic or inherited, isolated, segmental or generalized dystonia, with 27% of articles and 204.3 citations/paper. Conclusions: DBS in dystonia research is mainly published in a handful of scientific journals and focused on the outcomes of the surgery in idiopathic or inherited, isolated, segmental or generalized dystonia, and with globus pallidus internus as the main DBS target.

RESUMO Introdução: A distonia é uma doença heterogênea que, quando refratária ao tratamento medicamentoso, pode ter uma resposta favorável à estimulação encefálica profunda (EEP). Uma forma prática de ter uma visão desta área de pesquisa é por meio de análise bibliométrica, pois permite aos pesquisadores e terceiros a terem uma ideia das tendências e necessidades da área. Objetivo: Analisar os 100 artigos mais citados no tratamento de distonia pelo uso de EEP nos últimos 30 anos. Métodos: O protocolo de pesquisa foi realizado em junho de 2019 através da base de dados Scopus da Elsevier, em que se obteve os artigos mais citados na área de tratamento de distonia com EEP. Analisaram-se variáveis como autores, ano de publicação, país, afiliação, e alvos de EEP. Resultados: Os artigos foram principalmente publicados principalmente na Movement Disorders (19%), no Journal of Neurosurgery (9%), e na Neurology (9%). Os países europeus oferecem contribuições significativas (57% da amostra). A França (192,5 citações/artigo) e a Alemanha (144,1 citações/artigo) possuem as mais altas taxas de citações dentre todos os países. Os Estados Unidos contribuem com 31% dos artigos da amostra (129,8 citações/artigo). As publicações focaram em Desfechos gerais (46%), seguido de Desfechos a longo prazo (12,5%), e Complicações (11%). O principal tipo de distonia pesquisado foi distonia generalizada ou segmentar, idiopática ou hereditária, isolada, abrangendo 27% dos artigos e 204,3 citações/artigo. Conclusões: A pesquisa de EEP em distonia é publicada em seletos periódicos científicos e foca nos desfechos da cirurgia, nas distonias generalizadas ou segmentares, idiopáticas ou hereditárias, isoladas, sendo o globus pallidus internus o principal alvo da EEP.

How can neurophysiological studies help with movement disorders characterization in clinical practice? A review / Como os exames neurofisiológicos podem ajudar na caracterização dos transtornos do movimento na prática clínica? Uma revisão

ABSTRACT Background: Neurophysiological studies are ancillary tools to better understand the features and nature of movement disorders. Electromyography (EMG), together with electroencephalography (EEG) and accelerometer, can be used to evaluate a hypo and hyperkinetic spectrum of movements. Specific techniques can be applied to better characterize the phenomenology, help distinguish functional from organic origin and assess the most probable site of the movement generator in the nervous system. Objective: We intend to provide an update for clinicians on helpful neurophysiological tools to assess movement disorders in clinical practice. Methods: Non-systematic review of the literature published up to June 2019. Results: A diversity of protocols was found and described. These include EMG analyses to define dystonia, myoclonus, myokymia, myorhythmia, and painful legs moving toes pattern; EMG in combination with accelerometer to study tremor; and EEG-EMG to study myoclonus. Also, indirect measures of cortical and brainstem excitability help to describe and diagnose abnormal physiology in Parkinson's disease, atypical parkinsonism, dystonia, and myoclonus. Conclusion: These studies can be helpful for the diagnosis and are usually underutilized in neurological practice.

RESUMO Introdução: Os estudos neurofisiológicos são métodos auxiliares para compreender melhor as características e a natureza dos distúrbios do movimento. A eletromiografia (EMG), em associação com o eletroencefalograma (EEG) e o acelerômetro, podem ser utilizados para avaliar um espectro de movimentos hipo e hipercinéticos. Técnicas específicas podem ser aplicadas para melhor caracterizar a fenomenologia, ajudar a distinguir a origem psicogênica da orgânica e avaliar o local mais provável de geração do movimento no sistema nervoso. Objetivo: Pretendemos fornecer ao clínico uma atualização sobre ferramentas neurofisiológicas úteis para avaliar distúrbios do movimento na prática clínica. Métodos: Revisão não sistemática da literatura publicada até junho de 2019. Resultados: Uma diversidade de protocolos foi encontrada e descrita. Dentre eles, inclui-se o uso de EMG para a definição do padrão de distonia, mioclonia, mioquimia, miorritmia e painfull legs moving toes, além do uso de EMG em associação ao acelerômetro para avaliar tremor e, em associação ao EEG para avaliar mioclonia. Ademais, técnicas para medida indireta de excitabilidade cortical e do tronco encefálico ajudam a descrever e diagnosticar a fisiologia anormal da doença de Parkinson, parkinsonismo atípico, distonia e mioclonia. Conclusão: Esses estudos podem ser úteis para o diagnóstico e geralmente são subutilizados na prática neurológica.

Eminectomia para tratamento de luxação recidivante da ATM / Eminectomy for treatment of recurrent TMJ dislocation

Introdução: A luxação da articulação temporomandibular ocorre quando a cabeça da mandíbula se movimenta para fora da fossa articular, fazendo com que a superfície posterior da cabeça da mandíbula fique à frente da eminência articular. Quando ocorrem episódios frequentes, essa condição é referida como luxação recidivante. Embora existam diferentes tratamentos, a eminectomia apresenta-se como uma opção cirúrgica com resultados satisfatórios e prognóstico favorável. Relato de caso: Este trabalho relata o caso de uma paciente com quadro severo de luxações recidivantes associadas à distonia muscular, tratada cirurgicamente por eminectomia. A paciente apresenta acompanhamento de 36 meses, estável, sem sintomatologia ou novos episódios de luxação. A abordagem multidisciplinar apresenta um alto índice de sucesso, e procedimentos cirúrgicos devem ser considerados quando procedimentos clínicos falham. Considerações finais: A eminectomia mostra bons resultados no tratamento da luxação recidivante de ATM, com chances mínimas de recidiva ou danos articulares. Após a cirurgia, os pacientes mostram uma boa função articular... (AU)

Introduction: Dislocation of the temporomandibular joint occurs when the jaw head moves out of the joint fossa causing the posterior surface of the jaw head to be ahead of the joint eminence. When they occur in frequent episodes, this condition is referred like relapsing dislocation. Although there are different treatments, eminectomy presents as a surgical option with satisfactory results and favorable prognosis. Case report: This paper reports the case of a patient with severe recurrent dislocations associated with muscular dystonia, treated through surgical treatment of eminectomy associated with a clinical treatment protocol. The patient has a 36-month followup, stable, without symptoms or new episodes of dislocation. The multidisciplinary approach has a high success rate and surgical procedures should be considered when clinical procedures fail. Final considerations: Eminectomy shows good results in the treatment of recurrent TMJ dislocation, with minimal chances of recurrence or joint damage. After surgery, patients show good joint function... (AU)

Efectos adversos a nivel cardiovascular y neurológico asociados al consumo de modafinilo / Adverse effects at the cardiovascular and neurological level associated with the consumption of modafinil

Resumen Introducción: el modafinilo es un fármaco neuroestimulante utilizado principalmente para promover estados de vigilia atención y disminuir la fatiga ante ciertos comportamientos que propician la somnolencia diurna excesiva. Objetivo: identificar en la literatura científica los efectos adversos neurológicos y cardiovasculares causados por el consumo del modafinilo. Materiales y Métodos: revisión bibliográfica de los artículos encontrados entre los meses de abril y julio de 2019 en las bases de datos PUBMED, SCOPUS, DIALNET. 51 artículos superaron la evaluación de calidad metodológica y se incluyeron en la revisión. Resultados: se identificaron que los principales efectos adversos a nivel cardiovascular son la cardiomiopatía Tako-Tsubo y la taquicardia ventricular polimórfica, mientras que a nivel neurológico puede generar insomnio y distonías. Conclusiones: El consumo del modafinilo genera repercusiones en las funciones cognitivas y cardiovasculares por lo cual no es aconsejable su uso a largo plazo en personas sanas. MÉD. UIS.2020;33(1):31-8.

Abstract Introduction: modafinil is a neurostimulant drug used mainly to promote wakefulness, attention and decrease fatigue in certain behaviors that cause excessive daytime sleepiness. Objective: identify in the scientific literature the neurological and cardiovascular adverse effects caused by the consumption of modafinil. Materials and Methods: bibliographic review of the articles found between the months of April and July of 2019 in the PUBMED, SCOPUS, DIALNET databases. 51 articles passed the methodological quality assessment and were included in the review. Results: the main adverse effects at the cardiovascular level were identified as Tako-Tsubo cardiomyopathy and polymorphic ventricular tachycardia, while at the neurological level it can generate insomnia and dystonia. Conclusions: the consumption of modafinil generates repercussions on cognitive and cardiovascular functions, so its long-term use in healthy people is not advisable. MÉD.UIS.2020;33(1):31-8.

Specific characteristics of the medical history of swallowing before and after application of botulinum toxin in patients with cervical dystonia

OBJECTIVES: To compare signs and symptoms of dysphagia in individuals with cervical dystonia (CD) before and after application of botulinum toxin (BTX). METHODS: A prospective study was conducted with 20 patients diagnosed with CD with indications for BTX application. We selected 18 patients who met the study inclusion criteria. All individuals were patients from the Movement Disorders Unit, Department of Neurology, Federal University of São Paulo. BTX was applied in the cervical region at the necessary dose for each individual. To identify signs/complaints of changes in swallowing, we used a specific questionnaire that was completed by patients and/or their companions on the day of BTX injection and repeated 10 to 15 days after BTX injection. RESULTS: Among the 18 study subjects, 15 (83.3%) showed primary and three (16.7%) showed secondary cervical dystonia. The most frequent dystonic movements were rotation (18), tilt (5), forward shift (3), backward shift (7), shoulder elevation (12), shoulder depression (2), and cervical tremor (6). The main complaints reported before BTX application were voice changes in 10 (55.6%), need for adjustment of eating position in 10 (55.6%), coughing and/or choking while eating in nine (50%), and increased eating time in nine (50%) individuals. The main complaints reported after BTX application were coughing and/or choking while eating in 11 (61.1%), voice changes in nine (50%), sensation of food stuck in the throat in eight (44%), and increased eating time in eight (44%) individuals. CONCLUSION: The administration of a swallowing-specific questionnaire to individuals with CD before and after BTX application enabled the identification of possible dysphagia symptoms prior to drug treatment resulting from CD, which are often subsequently interpreted as side effects of the drug treatment. Thus, dysphagia can be managed, and aspiration symptoms can be prevented.

Perfil funcional de pacientes com distonia cervical: uma série de casos / Functional profile of patients with cervical dystonia: a series of cases

INTRODUÇÃO: A Distonia Cervical (DC) é uma doença dos núcleos da base e tem como consequência movimentos hipercinéticos, sendo a mais comum entre as distonias focais. Além disso, pode ser definida pela presença de contrações involuntárias envolvendo a musculatura cervical. OBJETIVO: descrever o perfil funcional de pacientes com DC, oferecendo maior embasamento focado nas habilidades funcionais desses pacientes. MÉTODOS: Foi realizado um estudo transversal de pacientes atendidos no Ambulatório de Neurociências localizado no Ambulatório Professor Francisco Magalhães Neto, Salvador, Bahia, no período de novembro a dezembro de 2017. RESULTADOS: Foram analisados 6 pacientes: 3 do sexo feminino e 3 do sexo masculino. A maior parte dos pacientes apresentou os sintomas iniciais após algum trauma sofrido, baixo/moderado risco de queda, qualidade de vida (QV) impactada negativamente por limitações físicas, dependência leve e dor moderada. As principais queixas relacionadas à participação social estavam relacionadas a frequentar ambientes públicos, devido à vergonha que sentem por causa dos movimentos involuntários, além da impossibilidade de trabalhar proporcionada pela doença. CONCLUSÕES: O perfil funcional dos pacientes com DC ainda é escasso na literatura. Nesse estudo, a população com DC mostrou sofrer não só impactos na QV por fatores físicos, mas, sobretudo, por fatores emocionais e sociais. [AU]

INTRODUCTION: Cervical Dystonia (CD) is a disease of the nuclei of the base and results in hyperkinetic movements, being the most common amongst focal dystonias. In addition, it can be defined by the presence of involuntary contractions involving the cervical musculature. OBJECTIVE: To make known the functional profile of patients with CD, offering a more focused foundation on the functional abilities of these patients. METHODS: A cross-sectional study was carried out of patients attended at the Neuroscience Outpatient Clinic located in the Professor Francisco Magalhães Neto Ambulatory, Salvador, Bahia, from November to December 2017. RESULTS: Six patients were analyzed: 3 females and 3 males. Most patients presented initial symptoms after some trauma, low/moderate risk of falls, quality of life (LQ) negatively impacted by physical limitations, mild dependence and moderate pain. The main complaints related to social engagement were related to attending public places, due to the shame that they feel because of the involuntary movements, besides the impossibility of working caused by the pathology. CONCLUSIONS: The functional profile of patients with CD is still scarce in literature. In this study, the population with CD showed not only impacts on LQ due to physical factors, but, above all, by emotional and social factors, which makes a biopsychosocial approach indispensable to the assistance of these persons. [AU]

Series de Pediatría Garrahan. El niño con problemas neurológicos / Garrahan Pediatrics Series. The child with neurological problems

Las afecciones neurológicas son uno de los motivos de consulta más frecuentes en la práctica pediátrica ambulatoria y ocupan un alto índice de las camas en la internación. El papel del pediatra en este contexto es muy complejo, ya que es quien recibe a un paciente en la emergencia o en el consultorio y debe estar atento a si un determinado síntoma o signo neurológico puede ser transitorio o el indicio de una enfermedad grave. Así, son fundamentales tanto el conocimiento de las distintas entidades neurológicas y de sus aspectos epidemiológicos y patogénicos como también el examen semiológico y los primeros estudios por realizar para la orientación diagnóstica, el tratamiento inicial, las indicaciones de derivación, la prevención de riesgos y el asesoramiento a los padres. Este nuevo volumen aborda esta temática especial con énfasis en el trabajo interdisciplinario y entre sus características se destacan: El estudio de importantes temas clínicos, como las convulsiones febriles, que se presentan en el 2% al 5% de los niños; la epilepsia infantil, con una prevalencia del 1%; la cefalea, cuya incidencia ha aumentado en los últimos veinte años y es hoy el motivo de consulta más frecuente en los servicios de neurología; las crisis paroxísticas no epilépticas, que aparecen entre el 5% y el 20% de la población infantil; el desafío diagnóstico del lactante hipotónico; las encefalopatías agudas, y los trastornos de la marcha y del movimiento. La inclusión, en todos los capítulos, de casos clínicos con su evolución y desenlace, textos destacados con los principales conceptos, puntos claves para recordar, además de material complementario, como bibliografía adicional, videos y enlaces a sitios web de interés. Una obra sólida y práctica, que transmite las experiencias de los profesionales de una institución del prestigio internacional del Hospital de Pediatría Prof. Dr. Juan P. Garrahan ­a treinta años de su creación- dedicada a todos los pediatras, donde quiera que trabajen al servicio de la salud de los niños.

Fisiopatología de la distonía / Pathophysiology of dystonia

RESUMEN La distonía es una entidad pobremente comprendida ya que a pesar que la era genómica ha proporcionado muchas pistas para la elucidación de los circuitos cerebrales responsables de este fenómeno, aún resta mucho por entender debido a que los modelos actuales son insuficientes para comprender a cabalidad esta entidad clínica.

SUMMARY Despite recent and relevant advances in the understanding of cerebral circuits involve in dystonia, there are many gaps to allow us to fully elucidate the phenomenon. The available data is insufficient to explain the different presentation and causes involved in the genesis of dystonia.

Genética de las distonías / Genetic classification of dystonia

RESUMEN Con el avance de la secuenciación genética y otras técnicas se ha logrado avanzar de manera significativa en la detección de formas monogénicas de la distonía así como en la contribución de varios factores genéticos en la génesis de esta condición.

SUMMARY With the refinement of genetic sequencing and many other techniques, monogenic forms of dystonia as well as various genetic contributions and epigenetic factors are now available to guide the clinician in the pursue of an accurate diagnosis of this condition.

Distonías secundarias / Secondary dystonia

RESUMEN Las distonías que se generan por una causa específica (secundaria), son menos frecuentes que las distonías primarias (genéticas). Las causas son multifactoriales, incluyendo lesiones puntuales en alguna estructura cerebral, así como toxinas, medicamentos o infecciones.

SUMMARY Dystonia emerging from a specific cause (secondary dystonia) are by far less frequent that genetic counterpart (primary dystonia). Some of these causes include focal brain lesions, toxins, drugs and infections among many others.

Manejo médico de la distonía / Medical management of dystonia

RESUMEN Para el manejo médico de la distonía se han utilizado tradicionalmente varios fármacos encaminados a disminuir esta condición y a mejorar la calidad de vida. Las terapias orales solas o combinadas proporcionan control parcial de los síntomas y en la mayoría de los casos hay que recurrir a terapias invasivas.

SUMMARY During the last years, several drugs has been tried in order to try to diminish the impact of this condition and improve the quality of life of patients who suffer from dystonia. Oral therapy alone or in combination, generates only partial symptom relief and most of the cases end up requiring other more invasive therapies.

Toxina botulínica en el manejo de las distonías / Botulinum toxins for dystonia

RESUMEN La toxina botulínica es actualmente en tratamiento de elección para las distonía focales y algunos segmentos del cuerpo en casos de distonía generalizada. Estos compuestos fueron utilizados por primera vez por oftalmólogos para el tratamiento de pacientes con estrabismo pero tiempo después se expandió su uso para indicaciones en neurología especialmente en distonía.

SUMMARY Botulinum toxins are nowadays the gold standard for treatment focal dystonia and some segments of the body in generalized dystonia. These compounds were first used by ophthalmologist in patients with strabismus but later on, they were widely spread in neurological indications especially dystonia.

Tratamiento quirúrgico de la distonía / Surgical management for dystonia

RESUMEN A pesar de los recientes avances en la comprensión de los circuitos cerebrales involucrados en la distonía, las técnicas quirúrgicas invasivas y no invasivas han fallado en proporcionar un beneficio substancial a los pacientes que sufren de distonía, en comparación con los resultados observados en la enfermedad de Parkinson, no obstante, la lesionectomía, la estimulación cerebral profunda y el ultrasonido enfocado pueden proporcionar mejoría en los casos refractarios al manejo médico.

SUMMARY Despite recent advances in understanding brain circuits involved in dystonia, surgical techniques both invasive and not invasive have fail to provide substantial benefit to patients suffering from dystonia compared to the results seeing in Parkinson's disease, nonetheless, lesionectomy, deep brain stimulation and focused ultrasound can provide relief in medical refractory cases.

Distonía psicógena / Psychogenic dystonia

RESUMEN La distonía psicógena (funcional) es una condición que representa un reto para el clínico, desde su terminología confusa hasta el tratamiento integral. Este fenómeno se presenta en pacientes con ausencia de una enfermedad neurológica o condición secundaria que explique cabalmente dicha presentación y generalmente con una comorbilidad psiquiátrica marcada.

SUMMARY Psychogenic (functional) dystonia represent a huge challenge to the clinician. Nowadays there is a discussion between which term fit most to this condition (psychogenic vs. functional) but so far a consensus has not been reach. This phenomenon is present in absence of any neurological condition or identifiable secondary cause and usually is accompanied with an important psychiatric comorbidity.

Discinesias paroxísticas / Paroxysmal dystonia

RESUMEN Existen enfermedades y condiciones que se presentan con movimientos involuntarios hipercinéticos de aparición súbita y remisión espontanea (episódicas). Dichas condiciones generan dificultades diagnósticas ya que por su carácter intermitente, en ocasiones no pueden ser evaluadas por el clínico.

SUMMARY During the last years, several drugs has been tried to try to diminish the impact of this condition and improve quality of life the people who suffer from dystonia. Oral therapy alone or in combination generates only partial symptom relief and most of the cases end up requiring other more invasive therapies.

Terapias no farmacológicas en distonías / Alternative therapies in dystonia

RESUMEN El uso de la medicina complementaria y alternativa está aumentando en todo el mundo, especialmente en los pacientes con enfermedades crónicas. En los tiempos de la medicina basada en la evidencia, en ocasiones se puede omitir el potencial beneficio de las terapias alternativas que no siempre pueden ser sometidas a la rigurosidad científica de los ensayos clínicos.

SUMMARY The use of complementary and alternative has spread in most part of the world, especially in patients with chronic disease. In evidence-based medicine times sometimes, the potential benefit of this kind of therapy may be overlook because this intervention may not be suitable to be tested with the actual scientific standards.